Answer:An ellipse is a closed curve consisting of points whose distances from each of two fixed points (foci) all add up to the same value .
Explanation:
Answer:Orbital period =21.22hrs
Explanation:
given that
mass of earth M = 5.97 x 10^24 kg
radius of a satellite's orbit, R= earth's radius + height of the satellite
6.38X 10^6 + 3.25 X10^7 m =3.89 X 10^7m
Speed of satellite, v= 
where G = 6.673 x 10-11 N m2/kg2
V= \sqrt (6.673x10^-11 x 5.97x10^ 24)/(3.89 X 10^ 7m)
V =10,241082.2
v= 3,200.2m/s
a) Orbital period
= 
V= 
T= 2
r/ V
= 2 X 3.142 X 3.89 X 10^7m/ 3,200.2m/s
=76,385.1 s
60 sec= 1min
60mins = 1hr
76,385.1s =hr
76,385.1/3600=21.22hrs
Answer:
a. Mass number is the sum of number of protons and neutrons present in the nucleus of an atom.
A = p + n
Charge is a unit of matter that tells how more or less the number of electrons are present as compared to number of protons in an atom. A positive charge means the atom lacks electrons.
Gamma rays are highly energetic electromagnetic rays. They have high penetrating power and are very difficult to shield owing to high energy.
b. The compete nuclear equation is:

This is a alpha decay process because alpha particle which is Helium atom is being produced. Francium is being formed after alpha particle is emitted.
c. The complete nuclear reaction is:

This is a positron emission process where in Rubidium is being formed.
Answer:
Yes
Explanation:
Yes because Electromagnetic waves differ from mechanical waves in that they do not require a medium to propagate. This means that electromagnetic waves can travel not only through air and solid materials, but also through the vacuum of space.